This invention pertains to floor cleaning and rug scrubbing machines, and more particularly to an improvement in such machines so that they are adaptable to the task of cleaning rugs whose characteristics are such that it is extremely difficult to reach down into their pile for thorough cleaning thereof.
An example of a rub scrubbing machine known in the prior art is that described in U.S. Pat. No. 2,640,211 to W. L. Petersen. The machine described in the Petersen patent involves the provision of a frame and cradle structure for supporting the brush, whereby the effective contact between the floor and brush surface may be controlled. The operative principle of such machine is the sliding of a frame back and forth on a fixed incline so as to vary the amount of contact of the forward side of the brush with a rug surface.
However, it has become necessary in light of developments in variously sculptured rugs, that is, rugs having wide variations in the depth of depressions formed therein, that a scrubbing machine be adapted to enable thorough cleaning of such rugs including the surfaces defining the depressions.
Accordingly, it is a primary object of the present invention to enable the thorough cleaning of rugs of the aforesaid character by permitting tilting of the brushes at selected angles.
Another object is to enable a difference in the tilt angle to be achieved while avoiding any objectionable tendency of the machine to creep or wander.
Another object is to simplify the means for adjusting the positioning of the brushes such that they can be moved out of contact with a rug surface.
Another object is to make the rug scrubbing machine adjustable to the task of waxing floors by permitting raising of the whole machine from the floor by the use of a brush having longer than normal size bristles. As a result the machine is entirely supported by the brushes.
A further object is to facilitate variation in the amount of contact or area of contact of the one side of the brush or brushes with the rug to be cleaned.
Yet another object of the present invention is to provide a rug scrubbing machine having rotary scrubbing brushes mounted so that their axes are generally upright, but which may be inclined at varying degrees from the vertical so that only one side of the brushes engages the rug.
An ancillary object is to provide the aforesaid tilting as required, but to accomplish this without any tendency toward binding, whereby the movement of the machine might be impeded.
Other and further objects, which specifically relate to the unique subject matter of the present continuation-in-part application, are to adapt the machine to low cost mass production and simple assembly. Moreover, to satisfy the demands for suitable aesthetic appearance and the ease of use requirements for a domestic appliance.
The above objects are fulfilled by a first feature of the present invention which permits the tilting of the frame carrying the brushes. More specifically, tilting is realized by pivotally mounting the front wheel of the machine; such mounting being preferably at the front wall of an integral housing for the machine.
Any tendency for the brushes to bind with the rug or other surface being cleaned is avoided because of the "free floating" provided for the brushes, that is to say, the brushes have a degree of freedom in the vertical direction because of the special construction of the brushes and cooperating parts. In particular, the brushes have hubs in which notches are formed. These notches are engageable with pins radially extending from spindles which operate to drive the brushes. Also provided on the spindles are ball detents which cooperate with suitable grooves in the brush hubs to hold the brushes on the spindles.
Other features relate specifically to the unique or non-common subject matter of the present continuation-in-part application. Such features were developed in consequence of the objects previously recited of adapting the general purposes of the machine to the particular requirements of household application. One of these features resides in the provision of a cam dial for accomplishing the objective of easy movability of the front wheel or roller so as to effect tilting of the machine.
The cam dial is mounted at the front of the machine housing and includes a plurality of stations, involving a plurality of detent positions, which are provided to accomplish the required height adjustment with a substantially uniform favorable ratio, (approximately a 12 to 1 ratio). Such a high ratio is deemed necessary because the combined weight of the polisher and the shampoo liquid is so great that a woman would have difficulty in adjusting the machine without this mechanical advantage.
Another novel feature, in accordance with the aforesaid adaptation of the basic cleaning machine to household use, is the provision of a spring-blade link which transmits the cam rise motion directly to a front wheel support, without lost motion. This spring-blade link is so constructed that the parts can be coupled by simply snapping them together. More specifically, the spring temper of this link is utilized to allow for relative displacement of the parts during the up and down travel of the front wheel support and, at the same time, to provide a convenient means for "snap lock" assembly. The latter provides a coupling which engages the parts so that both "pushing" and "pulling" forces are transmitted.
It will be apparent as the detailed description proceeds that the embodiment of the mechanism for providing tilting of the floor cleaner of the present continuation-in-part application differs from the earlier version of the parent application in that no follower spring is needed with the mechanism. Instead, the entire mechanism, which includes the aforesaid cam dial and link, and also the wheel support, are all carried by a base plate. As a result, there is no dependency for structural support on the cover of the machine. Such dependency is avoided with the present design and construction because it is desired to use plastic for the machine cover which would not be suitable for withstanding the stress encountered.
Yet another feature, in accordance with the present continuation-in-part application, resides in the provision of a splash guard adapted to prevent spraying, due to some centrifugal force primarily, of suds or shampoo during scrubbing of bare floors or during shampooing of carpets. Without such a guard, the suds and the like would be sprayed on the operators feet, which is obviously most undesirable, and also on any close-by objects. The uniqueness of the present splash guard is that it is extremely easily detachable, without the use of tools, in order that it may be cleaned or rinsed after use. In its specific construction these are provided two tabs which extend from the front wall of the guard structure, such tabs being lined up and hooked through to slots provided in the front skirt of the machine cover. It is arranged that the rear end of the guard is pushed upwardly such that it automatically engages two opposing shaft projections of the rear rollers. The splash guard is retained in place by means of a snap lock. Moreover, the splash guard is designed to float on the surface of carpets, but is automatically kept out of contact with bare floors when the machine is operated in any mode other than shampooing. For example, in the scrubbing mode, the front bottom of the guard is close to the floor, but still about 1/16 inch above the floor. Such design avoids any possibility of scratching or otherwise marring a surface which has been highly buffed.
The above and other related objects, features and advantages are achieved in accordance with a preferred embodiment of the invention illustrated in the accompanying drawing.